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jordan drops a penny off the empire state building. neglecting air resistance, how fast is the penny traveling after 6 seconds? how far has the penny fallen after 6 seconds?

User Hauron
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1 Answer

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The acceleration of gravity is 9.8 m/s². That means that when something
is falling here on Earth, its speed increases by 9.8 m/s every second that
it falls. In other words, whenever you look at it, it's falling 9.8 m/s faster
than it was falling one second earlier.

If you drop an object from some high place ... high enough that it can
keep falling for 6 seconds and not hit the ground yet ... it falls 9.8 m/s
faster every second, and at the end of 6 seconds, it's falling at

(6) x (9/8 m/s) = 58.8 meters per second.

At the beginning of the 6 seconds, its speed was zero.
At the end of the 6 seconds, its speed is 58.8 meters per second.
Its AVERAGE speed over the period of 6 seconds is

(1/2) (0 + 58.8 m/s)

= 29.4 meters per second .

Distance = (average speed) x (time)

= (29.4 m/s) x (6 sec)

= 176.4 meters .


BTW ... Jordan may be in trouble. I'm pretty sure it's illegal
in New York City to drop anything off of a tall building.
If someone happens to be walking by the building at that
particular moment, or 6 seconds later, getting hit in the head
by a penny falling at 58.8 m/s (about 132 mph !) can really
smart, and can muss your do for the rest of the day.
User BartBog
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7.5k points